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Introduction: Prompt defibrillation is critical during paediatric cardiac arrest. The main objective of this systematic review was to determine the initial defibrillation energy dose for ventricular fibrillation (VF) or pulseless ventricular tachycardia (pVT) that is associated with sustained return of spontaneous circulation (ROSC) during paediatric cardiac arrest. Associations between initial defibrillation energy dose with any ROSC, survival and defibrillation-induced complications were also assessed. Methods: A systematic review was performed using four databases (Medline, Embase, Web of Science, Cochrane Library) (PROSPERO: CRD42016036734). Human studies (cohort studies or controlled trials) and animal model studies (controlled trials) of pediatric cardiac arrest involving assessment of external defibrillation energy dosing were considered. The primary outcome was sustained ROSC. Two researchers independently reviewed all the titles and abstracts of the retrieved citations, selected the studies and extracted the data using a standardized template. Risk of bias of human non-randomised studies were assessed using the ROBIN-I tool (formerly ACROBAT-NRSI) tool proposed by the Cochrane Collaboration group. Results: The search strategy identified 14,471 citations of which 232 manuscripts were reviewed. Ten human and 10 animal model studies met the inclusion criteria. Human studies were prospective (n = 6) or retrospective (n = 4) cohort studies and included between 11 and 266 patients (median = 46 patients). Sustained ROSC rates ranged from 0 to 61% (n = 7). No studies reported a statistically significant association between the initial defibrillation energy dose and the rate of sustained ROSC (n = 7) or survival (n = 6). No human studies reported defibrillation-induced complications. Meta-analysis was not considered appropriate due to clinical heterogeneity. The overall risk of bias was moderate. All animal studies were randomized controlled trials with 8 and 52 (median = 27) piglets. ROSC was frequently achieved (more than 85%) with energy dose ranging from 2 to 7 joules/kg (n = 7). The defibrillation threshold varied according to the body weight and appears to be higher in infant models. Conclusion: Defibrillation energy doses and thresholds varied according to the body weight and trended higher for infants. No definitive association between initial defibrillation doses and the outcomes of sustained ROSC or survival could be demonstrated.
New simultaneous X-ray and radio observations of the archetypal mode-switching pulsar PSR B0943+10 have been carried out with XMM-Newton and the LOFAR, LWA and Arecibo radio telescopes in November 2014. They allowed us to better constrain the X-ray spectral and variability properties of this pulsar and to detect, for the first time, the X-ray pulsations also during the X-ray-fainter mode. The combined timing and spectral analysis indicates that unpulsed non-thermal emission, likely of magnetospheric origin, and pulsed thermal emission from a small polar cap are present during both radio modes and vary in a correlated way.
Introduction: Mild traumatic brain injury (mTBI) is a major cause of morbidity but there are no validated tools to help clinicians predict post-concussion symptoms. This systematic review and meta-analysis aimed to determine the prognostic value of S-100B protein to predict post-concussion symptoms following a mTBI in adults. Methods: The protocol of this systematic review was registered with the PROSPERO database (CRD42016032578). A search strategy was performed on seven databases (CINAHL, Cochrane CENTRAL, EMBASE, MEDLINE, Web of Knowledge, PyscBITE, PsycINFO) from their inception to October 2016. Studies evaluating the association between S-100B protein level and post-concussion symptoms assessed at least seven days after the mTBI were eligible. Individual patient data were requested. Studies eligibility assessment, data extraction and risk of bias assessment were performed independently by two researchers. Analyses were done following the meta-analysis using individual participant data or summary aggregate data guidelines from the Cochrane Methodology Review Group. Results: Outcomes were dichotomised as persistent (≥3 months) or early (≥7 days <3 months). Our search strategy yielded 23,298 citations of which 29 studies presenting between seven and 223 patients (n=2505) were included. Post-concussion syndrome (PCS) (16 studies), neuropsychological symptoms (9 studies) and health-related quality of life (4 studies) were the most frequently presented outcomes. The S-100B protein serum level of patients with no PCS was similar to that of patients experiencing persistent PCS (mean difference 0.00 [-0.05, 0.04]) or early PCS (mean difference 0.03 [-0.02, 0.08]). The odds of having persistent PCS (OR 0.56 (95% CI: 0.29-1.10) or early PCS (OR 1.67 (95% CI: 0.98-2.85) in patients with an elevated S-100B protein serum level was not significantly different from that of patients with normal values. No meta-analysis was performed for other outcomes than PCS due to heterogeneity and small samples. Studies’ overall risk of bias was considered moderate. Conclusion: Results suggest that the prognostic value of S-100B protein serum level to predict persistent and early post-concussion symptoms is limited. Variability in injury to S-100B protein sample time and outcomes assessed could potentially explain the lack of association and needs further evaluation.
Introduction: Mild traumatic brain injury (mTBI) is an understudied worldwide health problem and a socio-economic burden that remains a major cause of morbidity. However, there is no prognostication tool to help clinicians predict the occurrence of post-concussion symptoms. This systematic review aimed to determine the prognostic value of neuron-specific enolase (NSE) to predict post-concussion symptoms following a mTBI in adults. Methods: The protocol of this systematic review was registered with the International Prospective Register of Systematic Reviews (PROSPERO) database (registration number CRD42016033683). Seven databases (CINAHL, Cochrane CENTRAL, EMBASE, MEDLINE, PsycBITE, PsycINFO, Web of Knowledge/Biosis) were searched for cohort studies evaluating the association between NSE levels and post-concussion symptoms assessed at least seven days after the mild TBI. Grey literature was also screened using databases on dissertations and theses as well as abstracts from relevant congresses. Two researchers independently screened studies for inclusion, extracted data, and appraised their quality using the Quality in Prognostic Studies (QUIPS) tool from the Cochrane Collaboration Group. Results: Our search strategy yielded a total of 23,298 citations from which eight cohorts presented in 10 studies were included. Studies included between 45 and 141 patients (total=608 patients). The most frequently assessed outcomes were post-concussion syndrome (PCS) (13 assessments), neuropsychological disorders (10 assessments), return to work or sick leave (2 assessments) and Glasgow Outcome Scale (GOS) (2 assessments). No association was found between an elevated NSE serum level and the occurrence of PCS. Of the 33 outcomes assessments performed, only three showed an association between a higher level of serum NSE and a post-concussion symptom (alteration of at least three cognitive domains at 2 weeks, standardised physician assessment at 6 weeks and headache at 6 months following a mild TBI). Included studies’ overall risk of bias was considered moderate. Conclusion: Results of this systematic review conclude that based on current levels of evidence, serum NSE levels alone do not provide prognostic information on persistent or early post-concussion symptoms after a mTBI.
The evolution of the multipolar structure of the magnetic field of isolated neutron stars is studied assuming the currents to be confined to the crust. Lower orders (≤ 25) of multipole are seen to evolve in a manner similar to the dipole suggesting little or no evolution of the expected pulse shape. We also study the multifrequency polarization position angle traverse of PSR B0329+54 and find a significant frequency dependence above 2.7 GHz. We interpret this as an evidence of strong multipolar magnetic field present in the radio emission region.
Initiated Chemical Vapor Deposition (iCVD) is a well-known method for depositing polymers that are used in chemical, biological, and electrical applications. It is a variation of hot filament deposition and can used to produce conformal coatings of polymer films at relatively low reaction temperatures. It is also a solventless technique in which thin polymeric films are deposited by introducing controlled ratios of monomer and initiator gasses into the reaction chamber. Low temperatures in the reaction chamber allow the deposition of polymer films on a wide variety of substrates that include biological substrates.
We have simulated the growth of a monolayer of polymer films on two-dimensional surfaces using Monte Carlo simulation. We saw the formation of polymer chains over a time scale on the order of microseconds. We have assumed the substrate to be at room temperature while the reactor pressure close of 800 mTorr.
The grid on which we have simulated this polymer growth is represented by a 100x100 matrix, on which a series of specialized functions are executed in each time-step, or iteration. These functions can be divided into three categories: population, translation, and polymerization.
The goal of this simulation is to observe the initial growth of the iCVD surface reaction. We have obtained favorable results with the simulation and we are now looking to compare these results with experimental results for initiation growth.
The quasi-LO and quasi-TO modes of AlN crystallite were investigated. The analysis indicates that the Raman mode behavior concurs with Loudons’ model of mode-mixing in wurtzite (WZ) structure crystals which is due to the long-range electrostatic field. Phononlifetimes of GaN and AlN crystallites were studied via Raman lineshape. It was found that the low energy E2 mode lifetime is about an order of magnitude longer than that of the other modes, and that impurities impact significantly the phonon-lifetimes.
Ashok K. Dutt, Professor Emeritus in Geography, Planning and Urban Studies, University of Akron, USA,Vandana Wadhwa, Lecturer in the Department of Geography and Environment at Boston University, Massachusetts,Baleshwar Thakur, Former Head of the Department of Geography, Delhi School of Economics, University of Delhi,,Frank J. Costa, Professor Emeritus in Geography, Planning, Urban Studies and Public Administration at the University of Akron, USA.
The world has seen, and is still seeing the rapid development and spread of urban areas. Cities and towns have sprouted up every where around the globe. Villages are transforming into towns and towns into cities, attracting more and more people, and adding to urban expansion. Population increase and industrialization are the key factor behind such a phenomenal change in spatial structure.
India, the second most populated country in the world, has experienced large-scale development in and around its urban areas. The city of Kolkata (formerly Calcutta until 2001) in eastern India, the focus herein, has being aggressively multiplying in size over the last three decades. However, the rea population explosion took place between 1940 and 1950, during the Indian independence phase, although growth as such is still continuing (Chakraborty, 1990).
Closely associated with the morphology of any city are its past and present populations that have adhered to certain social and economic customs and followed distinctive occupations (Dutt et al., 1989, 151) Kolkata was the first major city developed by the British East India Company in the early 1700s. The East India Company built their first fortified construction, Fort William, to protect them from the other colonia aspirants. It was around this same fortified structure that the city of Kolkata grew and nurtured itself. It was a garrison town first, then the Company's town, next a provincial city, and later the headquarters of the British India government (National Atlas and Thematic Mapping Organisation (NATMO), 1996).
Two different atmospheric pressure microplasma systems are discussed and used for the synthesis and surface engineering of a range of nanomaterials. Specifically a gas-phase approach from vaporized tetramethylsilane has been used to synthesize silicon carbide nanoparticles with diameters below 10 nm. A different microplasma system that interfaces with a liquid solution has then been used for the synthesis of surfactant-free electrically stabilized gold nanoparticles with varying size. A similar microplasma-liquid system has been finally successfully used to tailor surface properties of silicon nanoparticles and to reduce graphene oxide into graphene. The synthesis and surface engineering mechanisms are also discussed.
To reduce prevalence of anaemia in low-income postpartum women.
A randomised, non-blind clinical trial was conducted among 959 low-income, postpartum women in eleven clinics in Mississippi. The clinics were randomised to one of three treatment groups: (i) selective anaemia screening of high-risk women as recommended currently (control); (ii) universal anaemia screening and treatment of anaemic women (group I); and (iii) universal Fe supplementation of 65 mg/d for two months to all low-income women (group II). All study participants within each clinic received the same treatment. Women were followed up at 6 months after delivery. Hb was measured at baseline and at follow-up. The primary outcome variable was the proportion of women with anaemia after treatment.
Eleven health clinics in Mississippi.
Low-income, postpartum women.
Baseline characteristics of the three study groups were compared using one-way ANOVA and an appropriate post hoc test for continuous variables and the χ2 test for categorical variables. Fifty-two per cent of postpartum women were anaemic (Hb < 12·0 g/dl) and the rate decreased to 33 % at 6 months after the intervention. Group II women, who received universal Fe supplementation, improved their Hb status significantly (P < 0·001) at 6 months postpartum compared with the other groups. Prevalence of anaemia was also significantly lower among group II women (22·5 %) compared with controls (34 %) and group I women (43 %; P < 0·001).
A universal Fe supplementation strategy was effective in reducing the prevalence of anaemia among low-income postpartum women.
We report on UV Raman spectroscopy of InxGa1−xN thin films grown on (0001) sapphire substrates using a specially designed metal-organic chemical vapor deposition (MOCVD) reactor. Eight films were examined in the compositional range 0<×<0.50. Mid and deep-UV Raman spectroscopy was done with the 325.2 nm line of the HeCd laser and the 244 nm line of a double frequency Ar ion laser. The mode behavior of the A1(LO) and E2 phonons was also investigated. We have found compelling evidence for one-mode behavior for the A1(LO) phonon mode, while our data for the E2 mode deviates from the predictions for one-mode behavior. The results for the A1(LO) mode are consistent with the previously reported phonon mode behavior in AlGaN alloys. Also, evidence regarding the presence of compositional inhomogeneities and spinodal decomposition in InGaN thin films is presented.
Mg ion-implantation of A12O3 wafers followed by air annealing at high temperatures was investigated as a way to provide bulk doped samples for studies of Mg surface segregation and its effect on surface mass transport. SIMS was used to analyse Mg concentrations in implanted and unimplanted near-surface regions and in the bulk. It was found that the concentration of Mg decreases dramatically with depth from both surfaces of an annealed wafer and is also observed in the bulk. These observations are attributed to bulk diffusion of the Mg combined with equilibrium surface segregation. Surface mass transport associated with the (1120) surface of an A12 O3 single crystal wafer doped and equilibrated by such a method was studied by the grating decay method; the Mg doped sample showed a decay rate in air higher than that in the undoped wafer by a factor of ∼ 2.4 at 1500°C.
a-Si:H films rf sputtered in 10 mT He and 0.5 mT H2, in contrast to those prepared in Ar/H2 or Xe/H2, exhibit port depositional oxidation when sputtered at power levels of 0.55 – 3.3 W/cm2 (100 – 600W). SEM measurements show that the morphology of the films evolves from a cracked, microcrystalline, glassy one at higher rf power levels to a porous one at low power levels. This trend is also correlated with a sharply increasing density of Si-H2 dihydride bonds at decreasing rf levels. Auger depth profiles of the oxygen concentration in the films agree with a diffusion controlled process of a source solute of O2 molecules into a semi-infinite solid solvent. Yet IR absorption measurements indicate that the oxygen is confined to the internal surfaces of the microvoids. The diffusion constant is a very sensitive functi n of the sputtering conditions. At low rf power levels, it is as low as 10−16 – 10−1 cm2 /sec at room temperature, but increases to ∼10−13 at 250 – 350°C.These results are discussed in terms of a porous network of microvoids, through which the O2 “squeezes” into the film.
Amorphous thin films of SixGe1-x:O (x = 0.70) were prepared by RF-sputtering at several substrate temperatures. The structural properties of these films were studied by IR spectroscopy and revealed features characteristic of hydrogen and/or oxygen bonded to silicon. The optical constants (n,k) were determined from reflection and transmission measurements at near-normal incidence for photon energies in the range of 1 eV and 2.6 eV. The optical gap was derived from the Taue plot and correlated with the composition of the samples. The increase of hydrogen and/or oxygen decreases the value of the refractive index and increases the optical gap.
The cw proton NMR spectra, spin lattice relaxation times Tx and free induction decay times T*2 were measured in various a-Si:H films deposited by rf-sputtering. All spectra exhibited broad and narrow components, of T*2 ∼ 20 and 45 μsec, respectively. In samples deposited at high rf power, the ratio of the integrated intensities of the broad and narrow lines was ∼ 1.5. These samples, which apparently contain mainly bulk monohydride bonds and a low volume fraction of microvoids, exhibit long-range H motion. In a sample deposited at low rf power, this ratio was ∼ 3. These samples, which contain significant dihydride and microvoid content, show a dramatic suppression of the long-range H motion. The T1 of both types of samples exhibits a clear minimum at ∼ 30 K, indicative of relaxation by H2 trapped in microvoids. The absolute values of T1, however, are smaller in the sample deposited at low rf power (0.1 sec at the minimum as opposed to 0.3 to 1.0 sec at the minimum), apparently due to a larger ratio of molecular hydrogen to bonded hydrogen. After annealing for 24 hours at 294°C, the ratio of broad-to-narrow components increases to > 10 in all samples, and the magnitudes of the T1 minima increase to about 1 sec in all samples.